Palletizer

Abstract

Apparatus is provided for arranging a row of bundles, preferably tied or untied bundles of folded or unfolded corrugated boxes or blanks, into stacks which include a plurality of layers of one or more bundles. The apparatus includes a feeding conveyor for feeding a row of bundles to a loading conveyor. A worker is stationed at the loading conveyor and functions to arrange the bundles into a layer on the loading conveyor. The loading conveyor then operates to transfer the layer of bundles to a transfer station on a vertical conveyor. Alternatively, the worker can arrange the bundles directly at the transfer station. The vertical conveyor includes a plurality of carrier plates which each operate to lift a layer of bundles from the transfer station and transfer it to a delivery station on the other side of the vertical conveyor. Each carrier plate includes a plurality of pushers so that the next carrier plate operates to push the layer of bundles from the delivery station onto a stripping conveyor which pushes the layer against a striker plate located above a downstacker. A stripping conveyor surrounds the downstacker and includes at least one opening therein through which the layer of bundles is deposited onto a movable platform of the downstacker or is deposited onto a layer of bundles which was previously deposited on the movable platform. The platform is incrementally actuated downwardly each time another layer of bundles is deposited thereon to form a stack of the desired height. The movable platform is then actuated downwardly to its discharge position, and the formed stack is then discharged from the downstacker, and straps are applied thereto. Actuating means are also provided for supplying control signals to the loading conveyor and the vertical conveyor to stop their operation while the platform is being lowered toward its discharge position and being returned to its uppermost position to receive the next layer of bundles.

What is claimed is: 
     
       1. Apparatus for organizing and arranging layers of one or more bundles into stacks, comprising: means responsive to a first control signal for supplying a layer of bundles to a transfer station at a loading elevation;   means for elevating and transferring said layer of bundles from said transfer station to a delivery station at a transferring elevation which is greater than the maximum elevation of the stack to be formed, said elevating and transferring means maintaining said layer substantially horizontally disposed during said elevating and transferring operation, said elevating and transferring means being operable to supply said first control signal to said supplying means to supply said layer of bundles to said transfer station;   stack-forming means adjacent said transferring means including a movable platform for sequentially receiving said layers from said delivery station to form a stack of layers on said movable platform, said platform being responsive to a second control signal to move between a receiving position and a discharge position;   first actuating means for supplying said second control signal to said platform to move said formed stack to said discharge position so that said formed stack may be discharged; and   said first actuating means also operating to supply a third control signal to said supplying means and a fourth control signal to said transferring means to interrupt the operation of said supplying means and said transferring means until said platform returns to said receiving position and is ready to receive the next layer of bundles from said delivery station.   
     
     
       2. Apparatus in accordance with claim 1 wherein said supplying means includes a loading conveyor on which bundles are arranged into layers of bundles. 
     
     
       3. Apparatus in accordance with claim 1 wherein said transferring means includes a conveyor for elevating said layers, said elevating conveyor having a plurality of carrier members for transferring said layers from said transfer station to said delivery station. 
     
     
       4. Apparatus in accordance with claim 3 wherein each of said carrier members includes spaced-apart members arranged to interlineate with and pass through spaced-apart members of said transfer station and said delivery station to transfer said layers from said transfer station to said delivery station. 
     
     
       5. Apparatus in accordance with claim 3 wherein said transfer station and said delivery station each include a plurality of spaced-apart members, and said carrier members each include a plurality of spaced-apart members, the spaced-apart members of said carrier members being arranged to interlineate with and pass through the spaced-apart members of said transfer station and said delivery station to transfer said layers from said transfer station to said delivery station. 
     
     
       6. Apparatus in accordance with claim 1 wherein said transferring means includes a sensor being operable to supply said first control signal to actuate said supplying means to supply said layer of bundles to said transfer station. 
     
     
       7. Apparatus in accordance with claim 3 wherein said transferring means includes a sensor for sensing the passage of each of said carrier members and being operable to supply said first control signal to actuate said supplying means to supply said layer of bundles to said transfer station. 
     
     
       8. Apparatus in accordance with claim 1 wherein said stack-forming means includes a downstacker surrounded by a conveyor for sequentially receiving said layers from said delivery station. 
     
     
       9. Apparatus in accordance with claim 8 wherein said downstacker conveyor includes at least one opening through which said layers of bundles are deposited on said movable platform. 
     
     
       10. Apparatus in accordance with claim 1 wherein said first actuating means includes a manually-controlled switch for supplying said second control signal to said platform and for supplying said third control signal to said supplying means and for supplying said fourth control signal to said transferring means. 
     
     
       11. Apparatus in accordance with claim 1 wherein said first actuating means includes a counter for automatically counting the number of layers deposited on said movable platform. 
     
     
       12. Apparatus in accordance with claim 11 further including a sensor disposed at said stack-forming means for sensing the deposit of a layer on said movable platform and being operable in response thereto to supply a signal to said counter. 
     
     
       13. Apparatus in accordance with claim 3 wherein said elevating conveyor includes a plurality of trackways and said carrier members each include a plurality of rollers for riding in said trackways so as to maintain said carrier members in a substantially horizontal position during the entire traverse of said carrier members between said transfer station and said delivery station. 
     
     
       14. Apparatus in accordance with claim 3 wherein said carrier members each include a plurality of pusher arms disposed thereon for pushing a layer of bundles from said delivery station to said stack-forming means. 
     
     
       15. Apparatus in accordance with claim 3 wherein said transferring means further includes a backstop assembly at said transfer station, said supplying means being operable to transfer said layer of bundles against said backstop assembly. 
     
     
       16. Apparatus in accordance with claim 15 wherein said backstop assembly includes a plurality of spaced-apart members arranged to interlineate with each of said carrier members as said carrier members pass through said transfer station. 
     
     
       17. Apparatus in accordance with claim 1 wherein said supplying means includes a sensor for sensing the passage of a layer of bundles to said transfer station and being operable in response thereto for intermittently stopping the operation of said supplying means. 
     
     
       18. Apparatus in accordance with claim 1 further including means disposed on said stack-forming means for sensing the return of said movable platform to said receiving position and being operable in response thereto to actuate said supplying means and said transferring means to transfer layers of bundles to said stack-forming means. 
     
     
       19. Apparatus for organizing and arranging layers of one or more bundles into stacks, comprising: a loading station for sequentially receiving layers of bundles;   means for sequentially elevating and transferring each of said layers from said loading station to a delivery station at a transferring elevation which is greater than the maximum elevation of the stack to be formed; said elevating and transferring means including a conveyor having carrier members which remain substantially horizontally disposed while elevating and transferring said layers to said delivery station;   stack-forming means adjacent said transferring means including means for sequentially receiving said layers from said delivery station to form a stack of layers, said receiving means being responsive to a first control signal to move between a receiving position and a discharge position;   first actuating means for supplying said first control signal to said receiving means so that said formed stack is transferred to said discharge position so that the formed stack may be discharged; and   said first actuating means also operating to supply a second control signal to said transferring means to discontinue the operation of said transferring means until said receiving means returns to said receiving position and is ready to receive the next layer of bundles from said delivery station.   
     
     
       20. Apparatus in accordance with claim 19 further including means for supplying said layers to said loading station. 
     
     
       21. Apparatus in accordance with claim 20 wherein said first actuating means also operates to supply a third control signal to said supplying means to interrupt the operation of said supplying means until said receiving means returns to said receiving position. 
     
     
       22. Apparatus in accordance with claim 21 wherein said transferring means is operable to supply a fourth control signal to actuate said supplying means to supply a layer of bundles to said loading station. 
     
     
       23. Apparatus in accordance with claim 19 further including second actuating means for energizing said transferring means to transfer said layers to said delivery station. 
     
     
       24. Apparatus in accordance with claim 23 wherein said second actuating means also operates to energize said stack-forming means. 
     
     
       25. Apparatus in accordance with claim 24 further including sensor means disposed at said stack-forming means for sensing the receipt of said layers and, in response thereto, for rendering operative said second actuating means. 
     
     
       26. Apparatus in accordance with claim 23 wherein said second actuating means is manually controlled. 
     
     
       27. Apparatus in accordance with claim 19 further including sensor means disposed at said stack-forming means for sensing the time period between layers received thereon and, in response thereto, said sensor means operating to control the speed of operation of said transferring means and said stack-forming means so that they are synchronized. 
     
     
       28. Apparatus in accordance with claim 19 further including sensor means disposed at said stack-forming means for sensing the receipt of a layer and, in response thereto, stopping the operation of said transferring means and said stack-forming means. 
     
     
       29. Apparatus in accordance with claim 19 wherein said stack-forming means including a lowering platform, sensor means disposed at said stack-forming means for sensing the receipt of a layer on said platform and, in response thereto, deenergizing said transferring means until said platform is ready to receive the next layer. 
     
     
       30. Apparatus in accordance with claim 19 further including counter means disposed at said loading station, said counter means operating to count the number of articles supplied to said loading station to form said one or more bundles, and in response thereto, to actuate said transferring means. 
     
     
       31. Apparatus in accordance with claim 19 further including sensor means disposed on said stack-forming means for sensing the position thereof and thereby synchronizing said stack-forming means and said transferring means. 
     
     
       32. Apparatus in accordance with claim 31 wherein said stack-forming means includes a conveyor having one or more openings formed therein, said conveyor surrounding said receiving means. 
     
     
       33. Apparatus in accordance with claim 20 further including a gravity feed conveyor for supplying bundles to said supplying means. 
     
     
       34. Apparatus for transferring a layer of articles from a first conveyor to a second conveyor, comprising: a first conveyor responsive to a first control signal for supplying a layer of articles to a transfer station at a loading elevation;   a second conveyor for elevating and transferring said layer of articles from said transfer station to a delivery station at an elevation which is greater than the maximum elevation of the stack to be formed, said second conveyor having means which remain substantially horizontally disposed while elevating and transferring said layer from said transfer station to said delivery station, said second conveyor being operable to supply said first control signal to actuate said first conveyor to supply said layer to said transfer station; and   said first conveyor including aa sensor for sensing the passage of a layer of articles to said transfer station and being operable in response thereto for intermittently stopping the operation of said first conveyor.   
     
     
       35. Apparatus in accordance with claim 19 wherein each of said carrier members includes spaced-apart members arranged to interlineate with and pass through spaced-apart members of said loading station and said delivery station to transfer said layers from said loading station to said delivery station. 
     
     
       36. Apparatus in accordance with claim 35 wherein said carrier members each include a plurality of pusher arms disposed thereon for pushing a layer of bundles from said delivery station to said stack-forming means. 
     
     
       37. Apparatus in accordance with claim 34 wherein each of said horizontal means includes carrier members having spaced-apart members arranged to interlineate with and pass through spaced-apart members of said transfer station and said delivery station to transfer said layers from said transfer station to said delivery station. 
     
     
       38. Apparatus in accordance with claim 37 wherein said carrier members each include a plurality of pusher arms disposed thereon for pushing a layer of bundles out of said delivery station. 
     
     
       39. Apparatus for moving layers of bundles to form stacks, comprising: means for elevating a layer from a first position to a raised position above said first position including means for maintaining said layer substantially horizontally disposed during said elevating operation;   means for horizontally transferring said layer from said raised position on said elevating means to a raised position of a stack-forming means, said means for horizontally transferring said layer being part of and movable with said elevating means; and   said stack-forming means including first means for sequentially receiving said layers from said raised position of said elevating means and for depositing said layers on a movable platform disposed at a second position lower than said raised position to form a stack of layers.   
     
     
       40. Apparatus in accordance with claim 39 further including means for supplying said layer of bundles to said elevating means when said elevating means is at said first position. 
     
     
       41. Apparatus in accordance with claim 39 wherein said elevating means includes a plurality of carrier members for elevating said layers from said first position to said raised position, and wherein said means for horizontally transferring said layer are said carrier means. 
     
     
       42. Apparatus in accordance with claim 41 wherein a transfer station is disposed at said first position and a delivery station is disposed at said raised position, and wherein said transfer station and said delivery station each include a plurality of spaced-apart members, and said carrier members each include a plurality of spaced-apart members, the spaced-apart members of said carrier members being arranged to interlineate with and pass through the spaced-apart members of said transfer station and said delivery station to transfer said layers from said first position to said raised position. 
     
     
       43. Apparatus in accordance with claim 39 wherein said stack-forming means includes a downstacker surrounded by a conveyor for sequentially receiving said layers from said elevating means and a striker plate against which said layer is pushed while it is deposited on said movable platform. 
     
     
       44. Apparatus in accordance with claim 43 wherein said downstacker conveyor includes at least one opening through which said layers of bundles are deposited onto said movable platform. 
     
     
       45. Apparatus in accordance with claim 41 wherein said elevating means includes a plurality of trackways and said carrier members each including a plurality of rollers for riding in said trackways so as to maintain said carrier members in a substantially horizontal position during the entire traverse of said carrier members between said first position and said raised position. 
     
     
       46. Apparatus for moving layers of bundles to form stacks, comprising: means for elevating a layer from a first position to a raised position above said first position including means for maintaining said layer substantially horizontally disposed during said elevating operation;   said elevating means including a plurality of carrier members for transferring said layers from said first position to said raised position;   said carrier members each include a plurality of pusher arms disposed thereon for pushing said layer from said raised position on said elevating means to a raised position of a stack-forming means; and   said stack-forming means including first means for sequentially receiving said layers from said raised position of said elevating means and for depositing said layers on a movable platform disposed at a second position lower than said raised position to form a stack of layers.   
     
     
       47. Apparatus in accordance with claim 39 further including control means for synchronizing the operation of said elevating means, and said stack-forming means. 
     
     
       48. Apparatus in accordance with claim 39 wherein said means for horizontally transferring includes means for pushing said layer from said raised position on said elevating means to said raised position of said stack-forming means. 
     
     
       49. Apparatus in accordance with claim 48 wherein said pushing means is part of said elevating means. 
     
     
       50. Apparatus in accordance with claim 39 further including a receiving station at the raised position of said elevating means for receiving said elevated layer, said means for horizontally transferring said layer including means for pushing said layer from said receiving station to said stack-forming means. 
     
     
       51. Apparatus in accordance with claim 41 wherein said carrier members each include a plurality of pushr arms disposed thereon for pushing a layer of bundles from said elevating means to said stack-forming means.